Prenatal cocaine exposure is a growing problem, especially among lower socioeconomic status, inner-city infants. Findings from experimental studies with animals have demonstrated that cocaine exposure in utero has an effect on the neurological development of the fetus. Previous research has related cocaine exposure to sensory motor abnormalities in human infants during the first few weeks, to months after birth, but no consistent pattern has emerged. The proposed research will investigate the influence of in utero cocaine exposure on early sensory motor processing. In addition, the proposed longitudinal study will investigate whether in utero cocaine exposure produces any long-tern effects on sensory motor development. The proposed study will investigate the maturation of sensory motor abilities in cocaine exposed infants recruited from an urban, lower socioeconomic status (SES), black population. The study will use a sequential longitudinal design to follow 149 randomly selected cocaine exposed infants from 4 months to 4 years old. These infants will be compared to a group of 149 healthy non-exposed infants matched on SES, race, gander, and gestational age. Progress in sensory motor, cognitive, and behavioral development will be assessed at 4 months, 1, 2, 3, and 4 years of age. In particular, it is expected that the cocaine exposed infants will show significant differences in sensory motor processing at 4 months, and that these differences will persists as deficits on standardized and norm referenced measures administered at the older age periods. Whereas previous studies have demonstrated that early gross measures of sensory motor ability in infants are not predictive of later functioning, it is hypothesized that later cognitive and behavioral abilities of the cocaine exposed infants will be significantly correlated with more discrete measure of early sensory motor performance. Data will be evaluated descriptively, as well as through a series of multivariate analyses of variance with repeated measures to describe the sensory motor functioning of infants exposed to cocaine, and to understand the developmental implications of exposure based on comparison to healthy, non-exposed infants. The proposed research will provide practical information that can be applied to intervention, as well as contribute to the theoretical understanding of sensory motor development in cocaine exposed infants.